The royal shared a never-before-seen photo of the pair on Instagram, which featured the duo dressed in casual attire.
Princess Eugenie was seen sporting a grey T-shirt and jeans, while the late monarch wore a tartan skirt along with a vest.
Aplaid skirt was a staple of the Queen’s wardrobe when she was in Scotland, and it is believed the picture was taken at her home in Balmoral.
“Thinking of you today,” Eugenie captioned the photo. “Missing you so much but remembering what a life of service, love and dedication to everyone and to your family, who loved you so very much.”
She continued: “Forever grateful to you. And always in my heart.”
In addition to Princess Eugenie, her mother Sarah Ferguson also shared a tribute on social media to the late Queen. Throughout Friday, the Duchess of York made three posts honouring the former monarch.
The first Instagram post featured a throwback photo of the Queen wearing a pale yellow dress. “You were a wonderful friend, a mentor, a second mother to me and grandmother to my daughters who share so much of your courage and heart,” Ferguson wrote in the caption. “You will always be loved and missed by our family and our nation.”
Another post from the Duchess of York included a quote from the Queen, which read: “Whatever life throws at us, our individual responses will be all the stronger for working together and sharing the load.”
Ferguson also shared how much the quote resonated with her, writing: “I often remember the wise words Her Late Majesty the Queen shared with me and the wider world. At a time of great troubles in the world one year after her passing, today this quote of hers seems more apt than ever.”
She gave fans an update on her two corgis, Sandy and Muick, as she shared a photo of herself playing with the two dogs in the grass. “As we mourn a year on, we also celebrate the wonderful times we shared with Her Late Majesty the Queen,” she wrote in the caption.
“She entrusted me with the care of her corgis Sandy and Muick and I am delighted to say they are thriving.”
The late Queen died on 8 September 2022 at Balmoral aged 96, after serving the British throne for 70 years. An emotional 11 days followed as the London Bridge plans swung into action - with a lying-in-state at Westminster Hall and a grand state funeral - all played out on a public stage.
On Friday, King Charles III and Queen Camilla were also among those paying their respects to the late monarch. The King and Queen attended a service of commemoration at Crathie Kirk, near Balmoral in Scotland. They were joined by the late Queen’s niece and nephew, Lady Sarah Chatto and the Earl of Snowdon.
The King also recorded a message and released a favourite photograph of his mother to mark the one-year anniversary of her death. Charles, in words written and audio spoken at Balmoral Castle, said he recalled with “great affection her long life, devoted service and all she meant to so many of us”.
He said: “I am deeply grateful, too, for the love and support that has been shown to my wife and myself during this year as we do our utmost to be of service to you all.”